import java.io.*;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.nio.charset.StandardCharsets;

public class HttpClient {

    public static String doGet(String httpUrl) {
        HttpURLConnection connection = null;
        // 输入流信息
        InputStream is = null;
        // 字符集
        BufferedReader br = null;
        // 返回结果字符串
        String result = null;
        try {
            // 创建远程url连接对象
            URL url = new URL(httpUrl);
            // 通过远程url连接对象打开一个连接, 强转成httpURLConnection类
            connection = (HttpURLConnection) url.openConnection();
            // 设置连接方式: get
            connection.setRequestMethod("GET");
            // 设置连接主机服务器的超时时间: 15000毫秒
            connection.setConnectTimeout(15000);
            // 设置读取远程返回的数据时间: 60000毫秒;
            connection.setReadTimeout(60000);
            // 发送请求
            connection.connect();
            // 通过connect连接, 获取输入流
            if (connection.getResponseCode() == 200) {
                is = connection.getInputStream();
                // 封装输入流is, 并指定字符集
                br = new BufferedReader(new InputStreamReader(is, "UTF-8"));
                // 存放数据
                StringBuffer sbf = new StringBuffer();
                String temp = null;
                while ((temp = br.readLine()) != null) {
                    sbf.append(temp);
                    sbf.append("\r\n");
                }
                result = sbf.toString();
            }
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // 关闭资源
            if (null != br) {
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            if (null != is) {
                try {
                    is.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            connection.disconnect();    // 关闭远程连接
        }
        return result;
    }

    public static String doPost(String httpUrl, String param) {
        HttpURLConnection connection = null;
        InputStream is = null;
        OutputStream os = null;
        BufferedReader br = null;
        String result = null;
        try {
            URL url = new URL(httpUrl);
            // 通过远程url连接对象打开连接
            connection = (HttpURLConnection) url.openConnection();
            // 设置连接请求方式
            connection.setRequestMethod("POST");
            // 设置连接主机服务器超时时间: 15000
            connection.setConnectTimeout(15000);
            // 设置读取主机服务器返回数据超时时间
            connection.setReadTimeout(60000);

            // 默认值: false, 当向远程服务器传送数据 / 写数据时, 需要设置为true
            connection.setDoOutput(true);
            // 默认值: true, 当前向远程服务读取数据时, 设置为true, 该参数可有可无
            connection.setDoInput(true);
            // 设置传入参数的格式: 请求参数应该是 name=value 的形式
            connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
            // 设置鉴权信息：Authorization: Bearer da3efcbf-0845-4fe3-8aba-ee040be542c0
            connection.setRequestProperty("Authorization", "Bearer da3efcbf-0845-4fe3-8aba-ee040be542c0");
            // 通过连接对象获取一个输出流
            os = connection.getOutputStream();
            // 通过输出流对象参数写出去 / 传输出去, 它是通过字节数组写出的
            os.write(param.getBytes(StandardCharsets.UTF_8));
            // 通过连接对象获取一个输入流, 向远程读取
            if (connection.getResponseCode() == 200) {
                is = connection.getInputStream();
                // 对输入流对象进行包装: charset 根据工作项目组的要求来设置
                br = new BufferedReader(new InputStreamReader(is, "UTF-8"));

                StringBuffer sbf = new StringBuffer();
                String temp = null;

                // 循环遍历一行一行读取数据
                while ((temp = br.readLine()) != null) {
                    sbf.append(temp);
                    sbf.append("\r\n");
                }
                result = sbf.toString();
            }
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // 关闭资源
            if (null != br) {
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            if (null != os) {
                try {
                    os.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            // 断开与远程地址url的连接
            connection.disconnect();
        }
        return result;
    }

    public static void main(String[] args) {
        String result = doGet("https://www.baidu.com");
        System.out.println(result);
    }
}
